1. Technical Field
The exemplary embodiments are directed towards an electrical junction box provided with an electric current sensor for detecting an electric current flowing in bus bars in a casing.
2. Background Art
Heretofore, various electrical junction box provided with such a kind of electric current sensor have been supplied.
For example, the present applicant has disclosed an electrical junction box in JP 2007-28773 A. In an electrical junction box 1 to be mounted in a motor vehicle, as shown in FIGS. 10A and 10B, a casing includes an upper casing 2 and a lower casing 3a containing in an upper part a laminated member 4 in which bus bars 4a are laminated alternately with insulation plates 4b, and containing an electric current sensor 5 below the laminated member 4. A special bus bar 6 penetrates a through-hole 5a in the sensor 5. The bus bar 6 is provided on opposite sides with bolt holes 6a to 6c. An output side bolt hole 6a is communicated with a bolt hole 7a in an output side bus bar 7 so that a bolt 8 secures the bus bars 6 and 7 to each other. A power source line terminal connected to a battery is connected to the input side bolt hole 6b by bolt-fastening while an input terminal of a fusible link is connected to the other input side bolt hole 6c by bolt-fastening.
However, because the laminated member 4 is disposed above the electric current sensor 5 in the electrical junction box 1 having the above construction, the electrical junction box 1 must be disassembled in order to remove the electric current sensor 5 from the electrical junction box 1, in the case where a malfunction occurs in the electric current sensor. Accordingly, there is a room to improve the electrical junction box in view of maintenance.
Also, because the electric current sensor 5 having a great calorific value is disposed in a bottom side of the casing, the electric current sensor is likely to easily increase a temperature in an internal space in the casing, thereby readily heat-affecting the bus bars and electrical components disposed above the electric current sensor. Accordingly, there is a room to improve the electrical junction box in view of heat radiation.